Home / Standards / JB/T 6840-1993 JB/T 6840-1993 Abolished 70mm电影放映机片夹 尺寸 Standard Type JB ICS N/A CCS N/A Status Abolished Issue Date 1993-07-09 Implementation 1994-01-01 Centralized Committee 机械工业部 Issuing Authority 机械工业部